Flextensional “moonie” actuators

Abstract

In recent years, piezoelectric and electrostrictive ceramics have been used in many actuators applications. A new type of composite actuator, which is based on the concept of a flextensional transducer, has been developed. (1-6) This ceramicmetal composite actuator, or "moonie" consists of either a piezoelectric ceramic disk or a multilayer stack sandwich between two specially designed metal end caps. This new design provides a sizeable displacement, as well as a large generative force. In other words, it bridges the gap between the two most common types of actuator; the multilayer and bimorph (7).

Enhanced magnetoelectric effect in Terfenol-D and flextensional cymbal laminates

“…The cymbal transducer is a class V flextensional transducer capable of tailoring ultrasound applications with near 40 times higher displacement and 40 times higher effective piezoelectric charge coefficient. [6][7][8] In this letter we report a novel ME laminate by using a flextensional cymbal as the piezoelectric layer placed between two magnetostrictive Terfenol-D plates. Their ME properties were measured and compared with the conventional T-T mode using PZT ceramic as the piezoelectric layer.…”

“…Details regarding the design and construction of the cymbal transducer can be found elsewhere. 7 In this work, the cymbal layer was prepared using the piezoelectric ceramic disk ͑PZT, Piezo Kinetics Inc.͒ and titanium end caps. The ceramic disk is 12.7 mm in diameter and 1.0 mm in thickness, poled in the thickness direction.…”

Electric-field-induced strain for (Bi1/2Na1/2)TiO3-based lead-free multilayer actuator

“…From this result, it is speculated that the large d 33 * (³850 pm/V) in the 10-layer specimen is also suspected due to the bending effect after applying 80 kV/cm. In other words, certain interfaces between Pt electrodes and piezoelectric active layers were delaminated by an induced high electric field at 80 kV/cm, and then, the piezoelectric active layers were partially bend similarly to a Moonie structure 40), 41) and a tailor-made multilayer piezoelectric actuator. 42), 43) …”

Desenvolvimento de técnicas de caracterização de transdutores piezelétricos.

“…Esses materiais são projetados como amplificadores acústicos e de deslocamento da cerâmica piezelétrica na direção 3, como mostra a Figura 1.1. A proposta desses dispositivosé de uso como atuadores [36,37,38,39,40], sonares [41] e hidrofones [42]. Por isso, neste trabalho serão chamados de atuadores piezelétricos flextensionais, ou simplesmente piezoatuadores flextensionais.…”

“…Um piezoatuador bilaminar pode chegar a deformações superiores a 1 mm [5], no entanto produz pouca força [78], enquanto que os piezoatuadores flextensional e de multicamadas cerâmicas em pilha são capazes de deformarem-se na mesma ordem e também produzirem força [37,79], ou seja, movem cargas.…”